urllib.request.urlopen can leak socket.timeout to callers

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-11-09.18:39:42.336>
labels = ['type-bug', 'library']
title = 'urllib.request.urlopen can leak socket.timeout to callers'
updated_at = <Date 2021-11-09.19:13:34.205>
user = 'https://github.com/thorpe-dev'

bugs.python.org fields:

activity = <Date 2021-11-09.19:13:34.205>
actor = 'thorpe-dev'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2021-11-09.18:39:42.336>
creator = 'thorpe-dev'
dependencies = []
files = []
hgrepos = []
issue_num = 45771
keywords = ['patch']
message_count = 1.0
messages = ['406038']
nosy_count = 1.0
nosy_names = ['thorpe-dev']
pr_nums = ['29499']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue45771'
versions = []